As mining activities expand deeper,deep high-temperature formations seriously threaten the future safe exploitation,while deep geothermal energy has great potential for development.Combining the formation cooling and ...As mining activities expand deeper,deep high-temperature formations seriously threaten the future safe exploitation,while deep geothermal energy has great potential for development.Combining the formation cooling and geothermal mining in mines to establish a thermos-hydraulic coupling numerical model for fractured formation.The study investigates the formation heat transfer behaviour,heat recovery performance and thermal economic benefits influenced during the life cycle.The results show that the accumulation of cold energy during the cold storage phase induces a decline in formation temperature.The heat recovery phase is determined by the extent of the initial cold domain,which contracts inward from the edge and decelerates the heat recovery rate gradually.With groundwater velocity increases,the thermal regulation efficiency gradually increases,the production temperature decreases,while the effective radius and thermal power increase first and then decrease.The injected volume and temperature significantly affect,with higher injection temperatures slowing thermal recovery,and the thermal regulation efficiency is more sensitive to changes in formation permeability and thermal conductivity.The heat extraction performance is positively correlated with all factors.The levelized cost of electricity is estimated at 0.1203$/(kW·h)during the cold storage.During the heat recovery,annual profit is primarily driven by cooling benefits.展开更多
Owing to the far-reaching environmental consequences of agriculture and food systems,such as their contribution to climate change,there is an urgent need to reduce their impact.International and national governments s...Owing to the far-reaching environmental consequences of agriculture and food systems,such as their contribution to climate change,there is an urgent need to reduce their impact.International and national governments set sustainability targets and implement corresponding measures.Nevertheless,critics of the globalized system claim that a territorial administrative scale is better suited to address sustainability issues.Yet,at the subnational level,local authorities rarely apply a systemic environmental assessment to enhance their action plans.This paper employs a territorial life cycle assessment methodology to improve local environmental agri-food planning.The objective is to identify significant direct and indirect environmental hotspots,their origins,and formulate effective mitigation strategies.The methodology is applied to the administrative department of Finistere,a strategic agricultural region in North-Western France.Multiple environmental criteria including climate change,fossil resource scarcity,toxicity,and land use are modeled.The findings reveal that the primary environmental hotspots of the studied local food system arise from indirect sources,such as livestock feed or diesel consumption.Livestock reduction and organic farming conversion emerge as the most environmentally efficient strategies,resulting in a 25%decrease in the climate change indicator.However,the overall modeled impact reduction is insufficient following national objectives and remains limited for the land use indicator.These results highlight the innovative application of life cycle assessment led at a local level,offering insights for the further advancement of systematic and prospective local agri-food assessment.Additionally,they provide guidance for local authorities to enhance the sustainability of planning strategies.展开更多
The industrial sector is the primary source of carbon emissions in China.In pursuit of meeting its carbon reduction targets,China aims to promote resource consumption sustainability,reduce energy consumption,and achie...The industrial sector is the primary source of carbon emissions in China.In pursuit of meeting its carbon reduction targets,China aims to promote resource consumption sustainability,reduce energy consumption,and achieve carbon neutrality within its processing industries.An effective strategy to promote energy savings and carbon reduction throughout the life cycle of materials is by applying life cycle engineering technology.This strategy aims to attain an optimal solution for material performance,resource consumption,and environmental impact.In this study,five types of technologies were considered:raw material replacement,process reengineering,fuel replacement,energy recycling and reutilization,and material recycling and reutilization.The meaning,methodology,and development status of life cycle engineering technology abroad and domestically are discussed in detail.A multidimensional analysis of ecological design was conducted from the perspectives of resource and energy consumption,carbon emissions,product performance,and recycling of secondary resources in a manufacturing process.This coupled with an integrated method to analyze carbon emissions in the entire life cycle of a material process industry was applied to the nonferrous industry,as an example.The results provide effective ideas and solutions for achieving low or zero carbon emission production in the Chinese industry as recycled aluminum and primary aluminum based on advanced technologies had reduced resource consumption and emissions as compared to primary aluminum production.展开更多
Upon infecting a host cell,the reticulate body(RB)form of the Chlamydia bacteria simply proliferates by binary fission for an extended period.Available data show only RB units in the infected cells 20 hours post infec...Upon infecting a host cell,the reticulate body(RB)form of the Chlamydia bacteria simply proliferates by binary fission for an extended period.Available data show only RB units in the infected cells 20 hours post infection(hpi),spanning nearly half way through the development cycle.With data collected every 4 hpi,conversion to the elementary body(EB)form begins abruptly at a rapid rate sometime around 24 hpi.By modeling proliferation and conversion as simple birth and death processes,it has been shown that the optimal strategy for maximizing the total(mean)EB population at host cell lysis time is a bang-bang control qualitatively replicating the observed conversion activities.However,the simple birth and death model for the RB proliferation and conversion to EB deviates in a significant way from the available data on the evolution of the RB population after the onset of RB-to-EB conversion.By working with a more refined model that takes into account a small size threshold eligibility requirement for conversion noted in the available data,we succeed in removing the deficiency of the previous models on the evolution of the RB population without affecting the optimal bang-bang conversion strategy.展开更多
Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realiz...Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realized the defect regulation of crystal NiCo_(2)S_(4) in the core.Taking advantage of the flexible protection of an amor-phous shell and the high capacity of a conductive core with defects,the v-NCS@MS electrode exhibited high specif-ic capacity(1034 mAh·g^(-1) at 1 A·g^(-1))and outstanding rate capability.Moreover,a hybrid supercapacitor was assembled with v-NCS@MS as cathode and activated carbon(AC)as anode,which can achieve remarkably high specific energy of 111 Wh·kg^(-1) at a specific power of 219 W·kg^(-1) and outstanding capacity retention of 80.5%after 15000 cycling at different current densities.展开更多
Pyrolysis is a rapidly expanding chemical-based recyclable method that complements physical recycling. It avoids improper disposal of post-consumer polymers and mitigates the ecological problems linked to the producti...Pyrolysis is a rapidly expanding chemical-based recyclable method that complements physical recycling. It avoids improper disposal of post-consumer polymers and mitigates the ecological problems linked to the production of new plastic. Nevertheless, while there is a consensus that pyrolysis might be a crucial technology in the years to come, more discussions are needed to address the challenges related to scaling up, the long-term sustainability of the process, and additional variables essential to the advancement of the green economy. Herein, it emphasizes knowledge gaps and methodological issues in current Life Cycle Assessment (LCA), underlining the need for standardized techniques and updated data to support robust decision-making for adopting pyrolysis technologies in waste management strategies. For this purpose, this study reviews the LCAs of pyrolytic processes, encompassing the complete life cycle, from feedstock collection to end-product distribution, including elements such as energy consumption, greenhouse gas emissions, and waste creation. Hence, we evaluate diverse pyrolysis processes, including slow, rapid, and catalytic pyrolysis, emphasizing their distinct efficiency and environmental footprints. Furthermore, we evaluate the impact of feedstock composition, process parameters, and scale of operation on the overall sustainability of pyrolysis-based plastic waste treatment by integrating results from current literature and identifying essential research needs. Therefore, this paper argues that existing LCA studies need more coherence and accuracy. It follows a thorough evaluation of previous research and suggests new insights into methodologies and restrictions.展开更多
Life Cycle Cost Analysis (LCCA) provides a systematic approach to assess the total cost associated with owning, operating, and maintaining assets throughout their entire life. BIM empowers architects and designers to ...Life Cycle Cost Analysis (LCCA) provides a systematic approach to assess the total cost associated with owning, operating, and maintaining assets throughout their entire life. BIM empowers architects and designers to perform real-time evaluations to explore various design options. However, when integrated with LCCA, BIM provides a comprehensive economic perspective that helps stakeholders understand the long-term financial implications of design decisions. This study presents a methodology for developing a model that seamlessly integrates BIM and LCCA during the conceptual design stage of buildings. This integration allows for a comprehensive evaluation and analysis of the design process, ensuring that the development aligns with the principles of low carbon emissions by employing modular construction, 3D concrete printing methods, and different building design alternatives. The model considers the initial construction costs in addition to all the long-term operational, maintenance, and salvage values. It combines various tools and data through different modules, including energy analysis, Life Cycle Assessment (LCA), and Life Cycle Cost Analysis (LCCA) to execute a comprehensive assessment of the financial implications of a specific design option throughout the lifecycle of building projects. The development of the said model and its implementation involves the creation of a new plug-in for the BIM tool (i.e., Autodesk Revit) to enhance its functionalities and capabilities in forecasting the life-cycle costs of buildings in addition to generating associated cash flows, creating scenarios, and sensitivity analyses in an automatic manner. This model empowers designers to evaluate and justify their initial investments while designing and selecting potential construction methods for buildings, and enabling stakeholders to make informed decisions by assessing different design alternatives based on long-term financial considerations during the early stages of design.展开更多
The success of catalytic schemes for the large-scale valorization of CO_(2) does not only depend on the development of active,selective and stable catalytic materials but also on the overall process design.Here we pre...The success of catalytic schemes for the large-scale valorization of CO_(2) does not only depend on the development of active,selective and stable catalytic materials but also on the overall process design.Here we present a multidisciplinary study(from catalyst to plant and techno-economic/lifecycle analysis)for the production of green methanol from renewable H2 and CO_(2).We combine an in-depth kinetic analysis of one of the most promising recently reported methanol-synthesis catalysts(InCo)with a thorough process simulation and techno-economic assessment.We then perform a life cycle assessment of the simulated process to gauge the real environmental impact of green methanol production from CO_(2).Our results indicate that up to 1.75 ton of CO_(2) can be abated per ton of produced methanol only if renewable energy is used to run the process,while the sensitivity analysis suggest that either rock-bottom H2 prices(1.5$kg1)or severe CO_(2) taxation(300$per ton)are needed for a profitable methanol plant.Besides,we herein highlight and analyze some critical bottlenecks of the process.Especial attention has been paid to the contribution of H2 to the overall plant costs,CH4 trace formation,and purity and costs of raw gases.In addition to providing important information for policy makers and industrialists,directions for catalyst(and therefore process)improvements are outlined.展开更多
Biochar-based bioenergy production and sub- sequent land application of biochar can reduce greenhouse gas emissions by fixing atmospheric carbon into the soil for a long period of time. A thorough life cycle assessmen...Biochar-based bioenergy production and sub- sequent land application of biochar can reduce greenhouse gas emissions by fixing atmospheric carbon into the soil for a long period of time. A thorough life cycle assessment of biochar-based bioenergy production and biochar land application in Northwestern Ontario is conducted using SimaPro Ver. 8.1. The results of energy consumption and potential environmental impact of biochar-based bioenergy production system are compared with those of conventional coal-based system. Results show that biocbar land application consumes 4847.61 MJ per tonne dry feedstock more energy than conventional system, but reduces the GHG emissions by 68.19 kg CO2e per tonne of dry feed- stock in its life cycle. Biochar land application improves ecosystem quality by 18 %, reduces climate change by 15 %, and resource use by 13 % but may adversely impact on human health by increasing disability adjusted life years by 1.7 % if biomass availability is low to medium. Replacing fossil fuel with woody biomass has a positiveimpact on the environment, as one tonne of dry biomass feedstock when converted to biochar reduces up to 38 kg CO2e with biochar land application despite using more energy. These results will help understand a comprehensive picture of the new interventions in forestry businesses, which are promoting biochar-based bioenergy production.展开更多
As one of the main structural units in a building,a solid wood floor has significant strategic research value for low-carbon energy saving.Taking the production line of a solid larch wood floor as a case study,we asse...As one of the main structural units in a building,a solid wood floor has significant strategic research value for low-carbon energy saving.Taking the production line of a solid larch wood floor as a case study,we assessed the environmental load during production based upon a life cycle assessment.Using GaBi 6.0 software,we analyzed the associated carbon sequestration during floor production,with the initial planting density serving as the disturbance factor in a modular analysis.The results indicated that the cutting and finishing steps have relatively intense,negative influences on the environment,whereas transportation,ripping,and trimming do not.Additionally,recycling biomass waste has the potential to reduce greenhouse gas emissions.When the initial planting density was 3.0×3.0 m,carbon sequestration was relatively high.Although the emissions of freshwater pollutants,volatile organic compounds,and fine particulate matter（matter with a 2.5-μm diameter） were comparatively high,the reduction of greenhouse gas emissions was still excellent at this planting density.展开更多
HFC-134a is a widely used environment-friendly refrigerant.At present,China is the largest producer of HFC-134a in the world.The production of HFC-134a in China mainly adopts the calcium carbide acetylene route.Howeve...HFC-134a is a widely used environment-friendly refrigerant.At present,China is the largest producer of HFC-134a in the world.The production of HFC-134a in China mainly adopts the calcium carbide acetylene route.However,the production route has high resource and energy consumption and large waste emission,and few of the studies addressed on the environmental performance of its production process.This study quantified the environmental performance of HFC-134a production by calcium carbide route via carrying out a life cycle assessment(LCA)using the CML 2001 method.And uncertainty analysis by Monte-Carlo simulation was also carried out.The results showed that electricity had the most impact on the environment,followed by steam,hydrogen fluoride and chlorine,and the impact of direct CO_(2) emissions in calcium carbide production stage on the global warming effect also could not be ignored.Therefore,the clean energy(e.g.,wind,solar,biomass,and natural gas)was used to replace coal-based electricity and coal-fired steam in this study,showing considerable environmental benefits.At the same time,the use of advanced production technologies could also improve environmental benefits,and the environmental impact of the global warming category could be reduced by 4.1%via using CO_(2) capture and purification technology.The Chinese database of HFC-134a production established in this study provides convenience for the relevant study of scholars.For the production of HFC-134a,this study helps to better identify the specific environmental hotspots and proposes useful ways to improve the environmental benefits.展开更多
The life cycle and annual production of four dominant species of Chironomids ( Chironomus plumosus, Chironomus sp., Clinotanypus sp., Tokunagayusurika akamusi) were studied with samples taken monthly in Biandantang La...The life cycle and annual production of four dominant species of Chironomids ( Chironomus plumosus, Chironomus sp., Clinotanypus sp., Tokunagayusurika akamusi) were studied with samples taken monthly in Biandantang Lake at eight stations from April, 1996 to March, 1997. Instar frequency data showed C. plumosus was univoltine, while the other three were bivoltine. Production in wet weight (g/(m 2·a)) calculated by the size frequency method for each species were: C. plumosus, 2.663 ; Chironomus sp.,1.161 ;Clinotanypus sp., 0.270; T. akamusi , 1.476. Based on the mean standing stock, their P/B ratios were 3.2, 4.0, 6.2 and 4.4, respectively.展开更多
Various kinds of data are used in new product design and more accurate datamake the design results more reliable. Even though part of product data can be available directlyfrom the existing similar products, there sti...Various kinds of data are used in new product design and more accurate datamake the design results more reliable. Even though part of product data can be available directlyfrom the existing similar products, there still leaves a great deal of data unavailable. This makesdata prediction a valuable work. A method that can predict data of product under development basedon the existing similar products is proposed. Fuzzy theory is used to deal with the uncertainties indata prediction process. The proposed method can be used in life cycle design, life cycleassessment (LCA) etc. Case study on current refrigerator is used as a demonstration example.展开更多
In this study, life cycle assessment of oxygen-18 by using cryogenic distillation of oxygen is performed using SimaPro 8.3 software. Life cycle assessment is performed to understand the environmental profile and hotsp...In this study, life cycle assessment of oxygen-18 by using cryogenic distillation of oxygen is performed using SimaPro 8.3 software. Life cycle assessment is performed to understand the environmental profile and hotspots of this process in order to be used in design and development. Simulation of oxygen-18 process is executed by Hysys software, and the required inputs and outputs for inventory of life cycle were acquired. By doing life cycle assessment and considering achieved results after characterization and normalization of inventory data it has been investigated that in the majority of environmental impacts electricity consumption has a huge contribution relative to other parts of the system like liquefied oxygen production from air separation unit,required facilities for air separation and oxygen-18 units, and needed transportation. Also, among 17 impact categories investigated in ReCiPe impact assessment method, fossil depletion, climate change(human health),particulate matter formation, climate change(ecosystem), human toxicity, and metal depletion have the most contribution in entire environmental loads respectively. Furthermore, sensitivity analysis showed that changing life cycle impact assessment method from ReCiPe to IMPACT 2002+ has no significant effect on acquired results and results are confident. In addition, assumption of market for depleted oxygen from heavy isotopes which is withdrawn from top of distillation columns showed some positive effects compared to first case and environmental impacts resulted from liquefied oxygen production(feed) reduced but because of huge contribution of electricity consumption compared to other sections, this positive effect has no remarkable influence on entire environmental loads of product system.展开更多
A laboratory experiment was performed to determine the feasibility of coupling a conventional wastewater treatment system with an algal photobioreactor (PBR) for the removal of nutrients from wastewater and production...A laboratory experiment was performed to determine the feasibility of coupling a conventional wastewater treatment system with an algal photobioreactor (PBR) for the removal of nutrients from wastewater and production of renewable resources. An activated sludge batch reactor was set up in series with an algal PBR to feed synthetic wastewater to Chlorella vulgaris. The nutrient concentration in the water as well as lipid content, carbohydrate content, and growth rate of the algal biomass were tested over 10 cycles to determine the capabilities of the coupled system. The study revealed complete nutrient removal in some cycles, with the average final nutrient content of 2 mg-P/L and 3 mg-N/L in effluent of the PBR. The algae biomass contained 24% ± 3% lipids and 26% ± 7% carbohydrates by dry weight. A life cycle assessment revealed the highest energy demand occurred during harvesting of the algal mixture through centrifugation or filtration, but the highest global warming and eutrophication impacts were due to CO2 use and PBR construction material production. It is feasible for the system to treat wastewater while generating renewable resources, but the system must be optimized to reduce life cycle environmental impacts and result in a net energy gain before large-scale implementation is possible.展开更多
The environmental planning and the current policy initiatives in European Union are aimed at continuous improvement of the productive fabric, heading toward a system in which the ＂quality＂ of products will no longer...The environmental planning and the current policy initiatives in European Union are aimed at continuous improvement of the productive fabric, heading toward a system in which the ＂quality＂ of products will no longer regardless of their environmental impacts. In this context, the methodology of LCA （life cycle assessment） is certainly one of the most innovative methods in the field of environmental protection as it allows evaluating the environmental burdens associated with a product, process or activity by identifying and quantifying material and energy consumption and environmental emissions. The objectives focus on finding the main impacts of the wine life cycle, as well as identifying crucial activities/stages in the wine production which establish the largest impacts. This paper＇s objective is to expose the advantages resulting from the use of the LCA method in the wine production sector, with a specific application to wine production in the Tuscany region.展开更多
Although the tobacco industry is a significant contributor to energy consumption and carbon emissions its negative environmental impact has received inadequate attention globally.Cigarette factories are a key link in ...Although the tobacco industry is a significant contributor to energy consumption and carbon emissions its negative environmental impact has received inadequate attention globally.Cigarette factories are a key link in the tobacco industry’s production chain,and using data provided by a cigarette factory in China we conduct a life cycle assessment to account for the carbon footprint of cigar production in cigarette factories.The results of the assessment show that factory air conditioning is the most important contributor to the environmental load of the cigar manufacturing process,while electricity is the key factor that contributes the greatest envi‐ronmental load across all of the processes in the product life cycle.In addition,packaging,including small boxes and cigarette cartons,has a significant impact on the industry’s environmental footprint due to its use of raw materials.We find the carbon footprint of the entire production process for cigar products to be 383.59 kg CO_(2) eq.Based on our findings,we suggest ways to optimize cigar/cigarette factory processes to re‐duce carbon emissions that can help to promote sustainable development in related industries.展开更多
This study covers the problem that most products become less competitive especially in the decline stages of their life cycle as most companies do not put adequate emphasis on using networked manufacturing systems in ...This study covers the problem that most products become less competitive especially in the decline stages of their life cycle as most companies do not put adequate emphasis on using networked manufacturing systems in the entire life cycle of a single product. The study employed a non-experimental approach to collect data. The research paper relied on secondary data for further analysis. The secondary sources used in this paper have been referenced progressively in the entire paper. The paper found that most companies are often faced with the challenge of coping with quality management in a product life cycle. Also, it found that networked manufacturing systems have provided a new paradigm for real-time monitoring and control at various life stages. The paper is divided as following parts： section 1 is about the background and problem statement. Section 2 comes through literature review including theoretical ＆ empirical review. Section 3 explains the procedures and methods that were used in carrying out the study. It explains how data collection was carried out and how data analysis was performed. Section 4 is about the results the paper found. Section 5 is a discussion of the results presented.展开更多
Cement industrial emissions account for 32% of air pollution in Cambodia. With that in mind, we examined the environmental impact of Cambodia’s cement industry and identified ways that it could reduce air pollution. ...Cement industrial emissions account for 32% of air pollution in Cambodia. With that in mind, we examined the environmental impact of Cambodia’s cement industry and identified ways that it could reduce air pollution. The study focused on raw material extraction and preparation, calcination, and cement preparation. Data for the life-cycle inventory were provided by the Kampot Cement Plant. Air emissions were assessed using EMEP/EEA and IPCC criteria, and the impact assessment used ReCiPe (2016). The baseline analysis revealed that calcination contributed the most air pollutants, so mitigation scenarios focused on alternative fuels only during the calcination stage of cement production: 1) 100% coal (S1);2) 93% coal and 7% biomass (S2);3) 85% coal and 15% biomass (S3);4) 70% coal and 30% biomass (S4);and 5) 50% coal and 50% biomass (S5). The results demonstrated that certain mitigation measures reduced major emissions and environmental damage. S5 had the best results, reducing CO<sub>2</sub> by 49.97, NOx by 2.233, and SO<sub>2</sub> by 49.333%;however, it increased PM<sub>2.5</sub> by 19.60% and total heavy metal (Pb, Cd, Hg, As, Cr, Cu, Ni, Se, Zn) output by 28.113%. The results of the study showed reductions in serious health and environmental effects associated with climate change of 48.83%, ozone generation of 9.62%, and particulate matter formation of 28.80%. However, carcinogenic and non-carcinogenic human toxicity increased by 35.66%. Therefore, such mitigation effect would be benefit to carbon reduction target in Cambodia.展开更多
Shorter product life cycles present new dressed in supply chain literature. This research challenges to managing production and logistics not adequately adaddresses issues pertaining to the management of supply chains...Shorter product life cycles present new dressed in supply chain literature. This research challenges to managing production and logistics not adequately adaddresses issues pertaining to the management of supply chains in a short life cycle environment. In this paper, we study the short life cycle environment; then we develop the ventory policy of the indirect manufacturer by explicitly using his demand us an output of the retailer＇s optimal inoptimal ordering policy. Finally, we also provide causes of the bullwhip effect in the context of short life cycle products.展开更多
基金financial support from the National Natural Science Foundation of China(Nos.52434006,52374151,and 51927808)。
文摘As mining activities expand deeper,deep high-temperature formations seriously threaten the future safe exploitation,while deep geothermal energy has great potential for development.Combining the formation cooling and geothermal mining in mines to establish a thermos-hydraulic coupling numerical model for fractured formation.The study investigates the formation heat transfer behaviour,heat recovery performance and thermal economic benefits influenced during the life cycle.The results show that the accumulation of cold energy during the cold storage phase induces a decline in formation temperature.The heat recovery phase is determined by the extent of the initial cold domain,which contracts inward from the edge and decelerates the heat recovery rate gradually.With groundwater velocity increases,the thermal regulation efficiency gradually increases,the production temperature decreases,while the effective radius and thermal power increase first and then decrease.The injected volume and temperature significantly affect,with higher injection temperatures slowing thermal recovery,and the thermal regulation efficiency is more sensitive to changes in formation permeability and thermal conductivity.The heat extraction performance is positively correlated with all factors.The levelized cost of electricity is estimated at 0.1203$/(kW·h)during the cold storage.During the heat recovery,annual profit is primarily driven by cooling benefits.
文摘Owing to the far-reaching environmental consequences of agriculture and food systems,such as their contribution to climate change,there is an urgent need to reduce their impact.International and national governments set sustainability targets and implement corresponding measures.Nevertheless,critics of the globalized system claim that a territorial administrative scale is better suited to address sustainability issues.Yet,at the subnational level,local authorities rarely apply a systemic environmental assessment to enhance their action plans.This paper employs a territorial life cycle assessment methodology to improve local environmental agri-food planning.The objective is to identify significant direct and indirect environmental hotspots,their origins,and formulate effective mitigation strategies.The methodology is applied to the administrative department of Finistere,a strategic agricultural region in North-Western France.Multiple environmental criteria including climate change,fossil resource scarcity,toxicity,and land use are modeled.The findings reveal that the primary environmental hotspots of the studied local food system arise from indirect sources,such as livestock feed or diesel consumption.Livestock reduction and organic farming conversion emerge as the most environmentally efficient strategies,resulting in a 25%decrease in the climate change indicator.However,the overall modeled impact reduction is insufficient following national objectives and remains limited for the land use indicator.These results highlight the innovative application of life cycle assessment led at a local level,offering insights for the further advancement of systematic and prospective local agri-food assessment.Additionally,they provide guidance for local authorities to enhance the sustainability of planning strategies.
基金supported by the National Key Research and Development Programs(2021YFB3704201 and 2021YFB3700902).
文摘The industrial sector is the primary source of carbon emissions in China.In pursuit of meeting its carbon reduction targets,China aims to promote resource consumption sustainability,reduce energy consumption,and achieve carbon neutrality within its processing industries.An effective strategy to promote energy savings and carbon reduction throughout the life cycle of materials is by applying life cycle engineering technology.This strategy aims to attain an optimal solution for material performance,resource consumption,and environmental impact.In this study,five types of technologies were considered:raw material replacement,process reengineering,fuel replacement,energy recycling and reutilization,and material recycling and reutilization.The meaning,methodology,and development status of life cycle engineering technology abroad and domestically are discussed in detail.A multidimensional analysis of ecological design was conducted from the perspectives of resource and energy consumption,carbon emissions,product performance,and recycling of secondary resources in a manufacturing process.This coupled with an integrated method to analyze carbon emissions in the entire life cycle of a material process industry was applied to the nonferrous industry,as an example.The results provide effective ideas and solutions for achieving low or zero carbon emission production in the Chinese industry as recycled aluminum and primary aluminum based on advanced technologies had reduced resource consumption and emissions as compared to primary aluminum production.
文摘Upon infecting a host cell,the reticulate body(RB)form of the Chlamydia bacteria simply proliferates by binary fission for an extended period.Available data show only RB units in the infected cells 20 hours post infection(hpi),spanning nearly half way through the development cycle.With data collected every 4 hpi,conversion to the elementary body(EB)form begins abruptly at a rapid rate sometime around 24 hpi.By modeling proliferation and conversion as simple birth and death processes,it has been shown that the optimal strategy for maximizing the total(mean)EB population at host cell lysis time is a bang-bang control qualitatively replicating the observed conversion activities.However,the simple birth and death model for the RB proliferation and conversion to EB deviates in a significant way from the available data on the evolution of the RB population after the onset of RB-to-EB conversion.By working with a more refined model that takes into account a small size threshold eligibility requirement for conversion noted in the available data,we succeed in removing the deficiency of the previous models on the evolution of the RB population without affecting the optimal bang-bang conversion strategy.
文摘Crystalline@amorphous NiCo_(2)S_(4)@MoS_(2)(v-NCS@MS)nanostructures were designed and constructed via an ethylene glycol-induced strategy with hydrothermal synthesis and solvothermal method,which simultaneously realized the defect regulation of crystal NiCo_(2)S_(4) in the core.Taking advantage of the flexible protection of an amor-phous shell and the high capacity of a conductive core with defects,the v-NCS@MS electrode exhibited high specif-ic capacity(1034 mAh·g^(-1) at 1 A·g^(-1))and outstanding rate capability.Moreover,a hybrid supercapacitor was assembled with v-NCS@MS as cathode and activated carbon(AC)as anode,which can achieve remarkably high specific energy of 111 Wh·kg^(-1) at a specific power of 219 W·kg^(-1) and outstanding capacity retention of 80.5%after 15000 cycling at different current densities.
文摘Pyrolysis is a rapidly expanding chemical-based recyclable method that complements physical recycling. It avoids improper disposal of post-consumer polymers and mitigates the ecological problems linked to the production of new plastic. Nevertheless, while there is a consensus that pyrolysis might be a crucial technology in the years to come, more discussions are needed to address the challenges related to scaling up, the long-term sustainability of the process, and additional variables essential to the advancement of the green economy. Herein, it emphasizes knowledge gaps and methodological issues in current Life Cycle Assessment (LCA), underlining the need for standardized techniques and updated data to support robust decision-making for adopting pyrolysis technologies in waste management strategies. For this purpose, this study reviews the LCAs of pyrolytic processes, encompassing the complete life cycle, from feedstock collection to end-product distribution, including elements such as energy consumption, greenhouse gas emissions, and waste creation. Hence, we evaluate diverse pyrolysis processes, including slow, rapid, and catalytic pyrolysis, emphasizing their distinct efficiency and environmental footprints. Furthermore, we evaluate the impact of feedstock composition, process parameters, and scale of operation on the overall sustainability of pyrolysis-based plastic waste treatment by integrating results from current literature and identifying essential research needs. Therefore, this paper argues that existing LCA studies need more coherence and accuracy. It follows a thorough evaluation of previous research and suggests new insights into methodologies and restrictions.
文摘Life Cycle Cost Analysis (LCCA) provides a systematic approach to assess the total cost associated with owning, operating, and maintaining assets throughout their entire life. BIM empowers architects and designers to perform real-time evaluations to explore various design options. However, when integrated with LCCA, BIM provides a comprehensive economic perspective that helps stakeholders understand the long-term financial implications of design decisions. This study presents a methodology for developing a model that seamlessly integrates BIM and LCCA during the conceptual design stage of buildings. This integration allows for a comprehensive evaluation and analysis of the design process, ensuring that the development aligns with the principles of low carbon emissions by employing modular construction, 3D concrete printing methods, and different building design alternatives. The model considers the initial construction costs in addition to all the long-term operational, maintenance, and salvage values. It combines various tools and data through different modules, including energy analysis, Life Cycle Assessment (LCA), and Life Cycle Cost Analysis (LCCA) to execute a comprehensive assessment of the financial implications of a specific design option throughout the lifecycle of building projects. The development of the said model and its implementation involves the creation of a new plug-in for the BIM tool (i.e., Autodesk Revit) to enhance its functionalities and capabilities in forecasting the life-cycle costs of buildings in addition to generating associated cash flows, creating scenarios, and sensitivity analyses in an automatic manner. This model empowers designers to evaluate and justify their initial investments while designing and selecting potential construction methods for buildings, and enabling stakeholders to make informed decisions by assessing different design alternatives based on long-term financial considerations during the early stages of design.
基金support from the King Abdullah University of Science and Technology(KAUST).T.Cordero-Lanzac and A.T.Aguayo acknowledge the financial support received from the Spanish Ministry of Science and Innovation with some ERDF funds(CTQ2016-77812-R)the Basque Government(IT1218-19)+2 种基金T.Cordero-Lanzac also acknowledges the Spanish Ministry of Education,Culture and Sport for the award of his FPU grant(FPU15-01666)A.Navajas and L.M.Gandía gratefully acknowledge the financial support from Spanish Ministerio de Ciencia,Innovación y Universidades,and the European Regional Development Fund(ERDF/FEDER)(grant RTI2018-096294-B-C31)L.M.Gandía also thanks Banco de Santander and Universidad Pública de Navarra for their financial support under“Programa de Intensificación de la Investigación 2018”initiative.
文摘The success of catalytic schemes for the large-scale valorization of CO_(2) does not only depend on the development of active,selective and stable catalytic materials but also on the overall process design.Here we present a multidisciplinary study(from catalyst to plant and techno-economic/lifecycle analysis)for the production of green methanol from renewable H2 and CO_(2).We combine an in-depth kinetic analysis of one of the most promising recently reported methanol-synthesis catalysts(InCo)with a thorough process simulation and techno-economic assessment.We then perform a life cycle assessment of the simulated process to gauge the real environmental impact of green methanol production from CO_(2).Our results indicate that up to 1.75 ton of CO_(2) can be abated per ton of produced methanol only if renewable energy is used to run the process,while the sensitivity analysis suggest that either rock-bottom H2 prices(1.5$kg1)or severe CO_(2) taxation(300$per ton)are needed for a profitable methanol plant.Besides,we herein highlight and analyze some critical bottlenecks of the process.Especial attention has been paid to the contribution of H2 to the overall plant costs,CH4 trace formation,and purity and costs of raw gases.In addition to providing important information for policy makers and industrialists,directions for catalyst(and therefore process)improvements are outlined.
基金supported by Natural Sciences and Engineering Research Council of Canada through Industrial Postgraduate Scholarships(NSERC-IPS)Ontario Graduate Scholarship (OGS)Ontario Power Generation(OPG)
文摘Biochar-based bioenergy production and sub- sequent land application of biochar can reduce greenhouse gas emissions by fixing atmospheric carbon into the soil for a long period of time. A thorough life cycle assessment of biochar-based bioenergy production and biochar land application in Northwestern Ontario is conducted using SimaPro Ver. 8.1. The results of energy consumption and potential environmental impact of biochar-based bioenergy production system are compared with those of conventional coal-based system. Results show that biocbar land application consumes 4847.61 MJ per tonne dry feedstock more energy than conventional system, but reduces the GHG emissions by 68.19 kg CO2e per tonne of dry feed- stock in its life cycle. Biochar land application improves ecosystem quality by 18 %, reduces climate change by 15 %, and resource use by 13 % but may adversely impact on human health by increasing disability adjusted life years by 1.7 % if biomass availability is low to medium. Replacing fossil fuel with woody biomass has a positiveimpact on the environment, as one tonne of dry biomass feedstock when converted to biochar reduces up to 38 kg CO2e with biochar land application despite using more energy. These results will help understand a comprehensive picture of the new interventions in forestry businesses, which are promoting biochar-based bioenergy production.
基金supported by the Science and Technology Support Project for the Twelfth Five-year Grant in China(Grant No.2015BAD14B05)
文摘As one of the main structural units in a building,a solid wood floor has significant strategic research value for low-carbon energy saving.Taking the production line of a solid larch wood floor as a case study,we assessed the environmental load during production based upon a life cycle assessment.Using GaBi 6.0 software,we analyzed the associated carbon sequestration during floor production,with the initial planting density serving as the disturbance factor in a modular analysis.The results indicated that the cutting and finishing steps have relatively intense,negative influences on the environment,whereas transportation,ripping,and trimming do not.Additionally,recycling biomass waste has the potential to reduce greenhouse gas emissions.When the initial planting density was 3.0×3.0 m,carbon sequestration was relatively high.Although the emissions of freshwater pollutants,volatile organic compounds,and fine particulate matter（matter with a 2.5-μm diameter） were comparatively high,the reduction of greenhouse gas emissions was still excellent at this planting density.
基金supported by the National Natural Science Foun-dation of China(22008198)and(21536009)Science and Technol-ogy Plan Projects of Shaanxi Province,China(2017ZDCXL-GY-10-03)Industrialization Cultivation Project of Education Ministry of Shaanxi province,China(19JK0854).
文摘HFC-134a is a widely used environment-friendly refrigerant.At present,China is the largest producer of HFC-134a in the world.The production of HFC-134a in China mainly adopts the calcium carbide acetylene route.However,the production route has high resource and energy consumption and large waste emission,and few of the studies addressed on the environmental performance of its production process.This study quantified the environmental performance of HFC-134a production by calcium carbide route via carrying out a life cycle assessment(LCA)using the CML 2001 method.And uncertainty analysis by Monte-Carlo simulation was also carried out.The results showed that electricity had the most impact on the environment,followed by steam,hydrogen fluoride and chlorine,and the impact of direct CO_(2) emissions in calcium carbide production stage on the global warming effect also could not be ignored.Therefore,the clean energy(e.g.,wind,solar,biomass,and natural gas)was used to replace coal-based electricity and coal-fired steam in this study,showing considerable environmental benefits.At the same time,the use of advanced production technologies could also improve environmental benefits,and the environmental impact of the global warming category could be reduced by 4.1%via using CO_(2) capture and purification technology.The Chinese database of HFC-134a production established in this study provides convenience for the relevant study of scholars.For the production of HFC-134a,this study helps to better identify the specific environmental hotspots and proposes useful ways to improve the environmental benefits.
文摘The life cycle and annual production of four dominant species of Chironomids ( Chironomus plumosus, Chironomus sp., Clinotanypus sp., Tokunagayusurika akamusi) were studied with samples taken monthly in Biandantang Lake at eight stations from April, 1996 to March, 1997. Instar frequency data showed C. plumosus was univoltine, while the other three were bivoltine. Production in wet weight (g/(m 2·a)) calculated by the size frequency method for each species were: C. plumosus, 2.663 ; Chironomus sp.,1.161 ;Clinotanypus sp., 0.270; T. akamusi , 1.476. Based on the mean standing stock, their P/B ratios were 3.2, 4.0, 6.2 and 4.4, respectively.
基金This project is supported by Ministry of Education, Culture, Sports, Science and Technology (MONBUSHO), Japan.
文摘Various kinds of data are used in new product design and more accurate datamake the design results more reliable. Even though part of product data can be available directlyfrom the existing similar products, there still leaves a great deal of data unavailable. This makesdata prediction a valuable work. A method that can predict data of product under development basedon the existing similar products is proposed. Fuzzy theory is used to deal with the uncertainties indata prediction process. The proposed method can be used in life cycle design, life cycleassessment (LCA) etc. Case study on current refrigerator is used as a demonstration example.
文摘In this study, life cycle assessment of oxygen-18 by using cryogenic distillation of oxygen is performed using SimaPro 8.3 software. Life cycle assessment is performed to understand the environmental profile and hotspots of this process in order to be used in design and development. Simulation of oxygen-18 process is executed by Hysys software, and the required inputs and outputs for inventory of life cycle were acquired. By doing life cycle assessment and considering achieved results after characterization and normalization of inventory data it has been investigated that in the majority of environmental impacts electricity consumption has a huge contribution relative to other parts of the system like liquefied oxygen production from air separation unit,required facilities for air separation and oxygen-18 units, and needed transportation. Also, among 17 impact categories investigated in ReCiPe impact assessment method, fossil depletion, climate change(human health),particulate matter formation, climate change(ecosystem), human toxicity, and metal depletion have the most contribution in entire environmental loads respectively. Furthermore, sensitivity analysis showed that changing life cycle impact assessment method from ReCiPe to IMPACT 2002+ has no significant effect on acquired results and results are confident. In addition, assumption of market for depleted oxygen from heavy isotopes which is withdrawn from top of distillation columns showed some positive effects compared to first case and environmental impacts resulted from liquefied oxygen production(feed) reduced but because of huge contribution of electricity consumption compared to other sections, this positive effect has no remarkable influence on entire environmental loads of product system.
文摘A laboratory experiment was performed to determine the feasibility of coupling a conventional wastewater treatment system with an algal photobioreactor (PBR) for the removal of nutrients from wastewater and production of renewable resources. An activated sludge batch reactor was set up in series with an algal PBR to feed synthetic wastewater to Chlorella vulgaris. The nutrient concentration in the water as well as lipid content, carbohydrate content, and growth rate of the algal biomass were tested over 10 cycles to determine the capabilities of the coupled system. The study revealed complete nutrient removal in some cycles, with the average final nutrient content of 2 mg-P/L and 3 mg-N/L in effluent of the PBR. The algae biomass contained 24% ± 3% lipids and 26% ± 7% carbohydrates by dry weight. A life cycle assessment revealed the highest energy demand occurred during harvesting of the algal mixture through centrifugation or filtration, but the highest global warming and eutrophication impacts were due to CO2 use and PBR construction material production. It is feasible for the system to treat wastewater while generating renewable resources, but the system must be optimized to reduce life cycle environmental impacts and result in a net energy gain before large-scale implementation is possible.
文摘The environmental planning and the current policy initiatives in European Union are aimed at continuous improvement of the productive fabric, heading toward a system in which the ＂quality＂ of products will no longer regardless of their environmental impacts. In this context, the methodology of LCA （life cycle assessment） is certainly one of the most innovative methods in the field of environmental protection as it allows evaluating the environmental burdens associated with a product, process or activity by identifying and quantifying material and energy consumption and environmental emissions. The objectives focus on finding the main impacts of the wine life cycle, as well as identifying crucial activities/stages in the wine production which establish the largest impacts. This paper＇s objective is to expose the advantages resulting from the use of the LCA method in the wine production sector, with a specific application to wine production in the Tuscany region.
基金supported by Shandong Natural Science Founda‐tion[Grant No.ZR2023MD079]Shandong Province Social Science Planning Research Project[Grant No.22CKRJ04]+2 种基金Taishan Scholar Project[Grant No.tsqn202103010]Department of Science and Tech‐nology of Shandong Province[Grant No.2021SFGC0904-05]Zaozhuang Science and Technology Bureau[Grant No.2021GH22].
文摘Although the tobacco industry is a significant contributor to energy consumption and carbon emissions its negative environmental impact has received inadequate attention globally.Cigarette factories are a key link in the tobacco industry’s production chain,and using data provided by a cigarette factory in China we conduct a life cycle assessment to account for the carbon footprint of cigar production in cigarette factories.The results of the assessment show that factory air conditioning is the most important contributor to the environmental load of the cigar manufacturing process,while electricity is the key factor that contributes the greatest envi‐ronmental load across all of the processes in the product life cycle.In addition,packaging,including small boxes and cigarette cartons,has a significant impact on the industry’s environmental footprint due to its use of raw materials.We find the carbon footprint of the entire production process for cigar products to be 383.59 kg CO_(2) eq.Based on our findings,we suggest ways to optimize cigar/cigarette factory processes to re‐duce carbon emissions that can help to promote sustainable development in related industries.
文摘This study covers the problem that most products become less competitive especially in the decline stages of their life cycle as most companies do not put adequate emphasis on using networked manufacturing systems in the entire life cycle of a single product. The study employed a non-experimental approach to collect data. The research paper relied on secondary data for further analysis. The secondary sources used in this paper have been referenced progressively in the entire paper. The paper found that most companies are often faced with the challenge of coping with quality management in a product life cycle. Also, it found that networked manufacturing systems have provided a new paradigm for real-time monitoring and control at various life stages. The paper is divided as following parts： section 1 is about the background and problem statement. Section 2 comes through literature review including theoretical ＆ empirical review. Section 3 explains the procedures and methods that were used in carrying out the study. It explains how data collection was carried out and how data analysis was performed. Section 4 is about the results the paper found. Section 5 is a discussion of the results presented.
文摘Cement industrial emissions account for 32% of air pollution in Cambodia. With that in mind, we examined the environmental impact of Cambodia’s cement industry and identified ways that it could reduce air pollution. The study focused on raw material extraction and preparation, calcination, and cement preparation. Data for the life-cycle inventory were provided by the Kampot Cement Plant. Air emissions were assessed using EMEP/EEA and IPCC criteria, and the impact assessment used ReCiPe (2016). The baseline analysis revealed that calcination contributed the most air pollutants, so mitigation scenarios focused on alternative fuels only during the calcination stage of cement production: 1) 100% coal (S1);2) 93% coal and 7% biomass (S2);3) 85% coal and 15% biomass (S3);4) 70% coal and 30% biomass (S4);and 5) 50% coal and 50% biomass (S5). The results demonstrated that certain mitigation measures reduced major emissions and environmental damage. S5 had the best results, reducing CO<sub>2</sub> by 49.97, NOx by 2.233, and SO<sub>2</sub> by 49.333%;however, it increased PM<sub>2.5</sub> by 19.60% and total heavy metal (Pb, Cd, Hg, As, Cr, Cu, Ni, Se, Zn) output by 28.113%. The results of the study showed reductions in serious health and environmental effects associated with climate change of 48.83%, ozone generation of 9.62%, and particulate matter formation of 28.80%. However, carcinogenic and non-carcinogenic human toxicity increased by 35.66%. Therefore, such mitigation effect would be benefit to carbon reduction target in Cambodia.
文摘Shorter product life cycles present new dressed in supply chain literature. This research challenges to managing production and logistics not adequately adaddresses issues pertaining to the management of supply chains in a short life cycle environment. In this paper, we study the short life cycle environment; then we develop the ventory policy of the indirect manufacturer by explicitly using his demand us an output of the retailer＇s optimal inoptimal ordering policy. Finally, we also provide causes of the bullwhip effect in the context of short life cycle products.
